We are planning an in-place upgrade of Linux level from RHEL 7 to RHEL 8 or RHEL 9. We have several PG clusters running on this server using different versions of postgres (pg12, pg13 and pg14).
We have couple of plans:
- Shutdown clusters, unmount disks that contain postgres data and wals, upgrade Linux, remount postgres disks and restart postgres clusters
- Same as above but reinstall postgres (pg12, pg13 and pg14) before restarting postgres clusters
- Will 1 or 2 or both above work?
- Is there any official documentation above OS upgrades?
Thank you for reading my post.